Default DOCSIS 1.0 ToS Overwrite

This document describes the Default DOCSIS 1.0 ToS Overwrite feature for the Cisco Cable Modem Termination System (CMTS). This feature eliminates the need to create multiple QoS profiles in order to perform type of service (ToS) overwrite by enabling a default ToS overwrite to be bound to all DOCSIS 1.0 Cable Modem (CM) created profiles.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.

Restrictions for Default DOCSIS 1.0 ToS Overwrite

The Default DOCSIS 1.0 ToS Overwrite feature is only applicable to CMs running DOCSIS version 1.0.

Once the Default DOCSIS 1.0 ToS Overwrite feature is configured, all CMs will need to be reset in order for the effect to take place.

Once the Default DOCSIS 1.0 ToS Overwrite feature is configured, all CMs will display the default values that were configured. After which, overwrite values can only be changed by editing the QoS profiles.

Information About Default DOCSIS 1.0 ToS Overwrite

To configure the Default DOCSIS 1.0 ToS Overwrite feature, you should
understand the following topic:

Default DOCSIS 1.0
ToS Overwrite Overview

Currently, ToS overwrite requires the
creation of static cable QoS profiles, which are assigned ToS fields and are
then associated with 1.0 CMs. This implementation works well if only a few
different service types are offered.

However,
scalability issues arises when large numbers of service types are presented;
each requiring a static QoS profile in order to perform ToS overwrite.

DOCSIS

Created by CableLabs, Data Over Cable Service Interface Specification (DOCSIS) defines the interface standards and requirements for all cable modems associated with high-speed data distribution over a cable television system network.

The DOCSIS architecture consists of the following two components:

Cable Modem (CM)

Cable Modem Termination System (CMTS)

Each of these components are situated at different locations, often with the CM located on a customer site and the CMTS on the service provider site, and communication between the CM and CMTS is conducted over cable through DOCSIS.

Note

Though there are several versions of DOCSIS available, the Default DOCSIS 1.0 ToS Overwrite feature is only applicable to CMs running DOCSIS 1.0.

Type-of-Service (ToS)

Tools such as type-of-service (ToS) bits identification make it possible to isolate network traffic by the type of application being used. ToS capabilities can be further expanded to isolate network traffic down to the specific brands, by the interface used, by the user type and individual user identification, or by the site address.

How to Configure Default DOCSIS 1.0 ToS Overwrite

The tasks in this section enables the use of the Default DOCSIS 1.0 ToS Overwrite feature.

Enabling Default DOCSIS 1.0 ToS Overwrite

All CMs with a DOCSIS 1.0 configuration file currently have their ToS
overwrite default values are set to tos-and: 0xff and tos-or: 0x00. Since there
were previously no mechanism in the DOCSIS 1.0 configuration file to specify
the ToS overwrite, QoS profiles were created and assigned to the default ToS
overwrites.

The following procedures enable the Default DOCSIS 1.0 ToS Overwrite
feature, which will allow a default ToS overwrite to be bound to all CM created
profiles.

Before You Begin

There are no prerequisites for these procedures.

Note

The Default DOCSIS 1.0
ToS Overwrite feature is only applicable to CMs running DOCSIS version 1.0.

Once the Default DOCSIS
1.0 ToS Overwrite feature is configured, all CMs will need to be reset in order
for the effect to take place.

Once the Default DOCSIS 1.0 ToS Overwrite feature is configured,
all CMs will display the default values that were configured. After which,
overwrite values can only be changed by editing the QoS profiles.

Procedure

Command or Action

Purpose

Step 1

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2

configureterminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3

cabledefault-tos-qos10tos-overwritetos-and
tos-or

Example:

Router(config)# cable default-tos-qos10 tos-overwrite 0x1F 0xE0

Configures the ToS overwrite default value for the CM. This
default value will be bound to all future CM created profiles.

Additional
References

Technical
Assistance

Description

Link

The
Cisco Technical Support & Documentation website contains thousands of pages
of searchable technical content, including links to products, technologies,
solutions, technical tips, tools, and technical documentation. Registered
Cisco.com users can log in from this page to access even more content.

Feature Information for Default DOCSIS 1.0 ToS Overwrite

Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http:/​/​www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Note

The table below lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Table 2 Feature Information for Default DOCSIS 1.0 ToS Overwrite

Feature Name

Releases

Feature Information

Default DOCSIS 1.0 ToS overwrite

Cisco IOS XE Everest 16.6.1

This feature was integrated into Cisco IOS XE Everest 16.6.1 on the Cisco cBR Series Converged Broadband Routers.